Heated fluid regulators

ABSTRACT

Example apparatus for regulator heat transfer are disclosed. An example apparatus includes a housing including an inlet, an outlet, a first valve, and a stem disposed therein. The example apparatus includes a vortex generator disposed in the housing. A fluid is to flow from the inlet through the vortex generator. The example apparatus includes a second valve disposed in the vortex generator. In the example apparatus, the vortex generator is to generate heat prior to the fluid flowing through the second valve to the outlet. The stem is to control the first valve and the second valve to regulate an amount of the heat conveyed to the first valve.

RELATED APPLICATION

This patent arises from a continuation of U.S. application Ser. No.13/926,687 titled “Heated Fluid Regulators,” and filed on Jun. 25, 2013.U.S. application Ser. No. 13/926,687 is incorporated herein by thisreference in its entirety.

FIELD OF THE DISCLOSURE

This disclosure relates generally to fluid regulators and, moreparticularly, to heated fluid regulators.

BACKGROUND

Fluid regulators may experience icing from hydrates at a point ofpressure reduction. In some cases, this icing may occur at temperaturesabove freezing. Ice may build up in the regulator, thereby hinderingperformance of the regulator.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a first apparatus according to one or moreaspects of the present disclosure.

FIG. 2 is a graphical depiction of flow of a fluid through an examplevortex generator versus a temperature difference between the fluidflowing through the vortex generator and an input fluid.

FIG. 3 is a schematic view of a second apparatus according to one ormore aspects of the present disclosure.

FIG. 4 is a schematic view of a third apparatus according to one or moreaspects of the present disclosure.

FIG. 5 is a cross-sectional view of the third apparatus of FIG. 4.

FIG. 6 is a schematic view of a fourth apparatus according to one ormore aspects of the present disclosure.

The figures are not to scale. Instead, to clarify multiple layers andregions, the thickness of the layers may be enlarged in the drawings.Wherever possible, the same reference numbers will be used throughoutthe drawing(s) and accompanying written description to refer to the sameor like parts. As used in this patent, stating that any part (e.g., alayer, film, area, or plate) is in any way positioned on (e.g.,positioned on, located on, disposed on, or formed on, etc.) anotherpart, means that the referenced part is either in contact with the otherpart, or that the referenced part is above the other part with one ormore intermediate part(s) located therebetween. Stating that any part isin contact with another part means that there is no intermediate partbetween the two parts.

SUMMARY

Heated fluid regulators are disclosed. An example apparatus includes ahousing including an inlet, an outlet, a first valve, and a stemdisposed therein. The example apparatus includes a vortex generatordisposed in the housing. A fluid is to flow from the inlet through thevortex generator. The example apparatus includes a second valve disposedin the vortex generator. In the example apparatus, the vortex generatoris to generate heat prior to the fluid flowing through the second valveto the outlet. The stem is to control the first valve and the secondvalve to regulate an amount of the heat conveyed to the first valve

An example regulator includes a body having an inlet, an outlet, a firstvalve, and a stem disposed therein. A fluid is to flow from the inlet tothe outlet. The example regulator includes a vortex tube to heat thefluid prior to the fluid flowing through the first valve. In the exampleregulator, the stem and at least a portion of the vortex tube aredisposed in an interior of the body. The example regulator includes asecond valve disposed in the vortex tube. In the example regulator, thestem is to control the first valve and the second valve to regulate anamount of the fluid flowing from the vortex tube to the first valve.

Another example apparatus includes means for regulating pressure of afluid and means for heating the means for regulating pressure. Theexample apparatus includes first means for controlling a first flow ofthe fluid from the means for heating to the means for regulatingpressure and second means for controlling a second flow of the fluid atthe means for regulating pressure. The example apparatus includes meansfor positioning the first means for controlling and the second means forcontrolling. In the example apparatus, the means for regulatingpressure, the means for heating, and the means for positioning aredisposed in one body.

DETAILED DESCRIPTION

The example apparatus disclosed herein relate to heated fluidregulators. More specifically, the examples described herein may be usedto provide heat to a fluid regulator without requiring external heatingsources. In particular, the examples described herein employ a vortexgenerator within a body of the regulator, where the vortex generator isto convey heat to the regulator to prevent icing within the regulator.

Hydrates, or a frozen mixture of water and hydrocarbons, form when, forexample, water and natural gas are in contact at low temperatures andunder high pressure. Additional factors that may contribute to hydrateformation include, for example, high fluid velocities, fluid agitation,pressure pulsations, and the presence of carbon dioxide and/or hydrogensulfide. Icing due to hydrates may result as a hydrocarbon fluidcontaining, for example, water and carbon dioxide, flows through aregulator. When the pressure of the fluid is reduced in accordance withthe operation of the regulator, the temperature of the fluid is alsoreduced according to the Joule-Thomson effect. As a result of thetemperature drop, any moisture in the fluid stream may result in theformation of hydrates. Hydrates may form, for example, at a point ofpressure reduction in the regulator, such as at a valve of theregulator.

A build-up of, for example, hydrates in the regulator may hinder theperformance of the regulator. For example, a build-up of hydrates at theregulator valve may prevent the regulator valve from closing or openingproperly, thereby affecting the ability of the regulator to control thepressure of the fluid in response to varying demand on the regulator.Icing in the regulator may further impede the fluid output of theregulator by, for example, clogging the regulator outlet.

While some known applications of regulators involving fluids that mayform hydrates have included heat sources to reduce instances of icing,such heat sources are typically additional devices that are mountedexternal to a body of the regulator. One such external heat source is avortex generator. Vortex generators produce heat by rotating acompressed fluid (e.g., compressed air) through, for example, a tube, athigh speeds to generate a vortex. The resulting vortex includes a hotfluid stream, a portion of which may exit through an outlet of thevortex generator. A remaining portion of the vortex fluid is forced backdown the tube of the vortex generator at a slower rate so that heat inthe slower moving fluid is transferred to the faster moving incomingfluid. This transfer of heat results in a cold fluid stream that exitsthe vortex tube at an outlet opposite the outlet of the hot fluidstream. The flow of the hot fluid stream and the flow of the cold fluidstream through the respective outlets may be regulated by valves.

In accordance the teachings disclosed herein, a vortex generator and aregulator are disposed within a regulator body. A hot fluid stream isgenerated by the vortex generator and exits through an outlet disposedproximate to a valve of the regulator to provide heat to the regulatorvalve to prevent icing during operation of the regulator. Specifically,the heat generated by the vortex generator and transferred to theregulator valve may prevent icing due to the formation of hydrates atthe point of pressure reduction within the regulator. In some examples,heat may be transferred to the regulator valve via, for example,conduction, fluid mixing, and/or via a fluid flowing serially throughthe vortex generator and the regulator. Further, a two-seat, single stemvalve design provides for concurrent control of the regulator and thevortex generator in the regulator body.

Turning now to the figures, FIG. 1 depicts an example apparatus 100including a regulator 102 having a first regulator chamber 102 a and asecond regulator chamber 102 b disposed in a regulator body 104. Aprocess fluid, for example, natural gas or compressed air, enters aprocess fluid inlet 106 and flows into the first regulator chamber 102a. A regulator valve 108 is disposed between the regulator chambers 102a, 102 b to regulate a pressure of the process fluid flowing through theregulator 102.

The regulator valve 108 is controlled by a stem 110 disposed in theregulator body 104. The stem 110 opens and closes the regulator valve108 to provide a substantially constant output pressure of the processfluid at a regulator outlet 112. The stem 110 controls the regulatorvalve 108 in response to a force generated by a loading mechanism 114and detected by a sensing element 116. The stem 110 is communicativelyconnected to the sensing element 116 and displacement of the sensingelement 116 due to a force generated by the loading mechanism 114 causesthe stem 110 to open the regulator valve 108. In the apparatus 100, theloading mechanism 114 includes a spring and the sensing element 116 is adiaphragm. In some examples, the regulator 102 is a pressure-loaded ordome-loaded regulator or a weight-loaded regulator. In further examples,the loading mechanism 114 includes a combination of spring loading, domeloading, and/or weights. The sensing element 116 may comprise, forexample, an elastomeric material, pistons, or bellows.

Additionally, a vortex tube 118 is disposed in the regulator body 104.An input fluid enters the vortex tube 118 through vortex tube inlets 120a, 120 b. Although FIG. 1 shows the apparatus 100 having two vortex tubeinlets 120 a, 120 b, the apparatus 100 may have fewer or more vortextube inlets. Further, the input fluid may be the same fluid as theprocess fluid entering the process fluid inlet 106 of the regulator 102or a different fluid than the process fluid.

The vortex tube inlets 120 a, 120 b include nozzles 121 to spin theinput fluid to generate a vortex as the input fluid flows into thevortex tube inlets 120 a, 120 b. In some examples, the nozzles 121comprise tangential inlets or inlets having an Archimedes spiral shape.The nozzles 121 may comprise one or more inlets to spin the input fluid.Spinning the input fluid as the input fluid enters the vortex tubeinlets 120 a, 120 b through nozzles 121 increases the tangentialvelocity of the input fluid as the input fluid flows from the vortextube inlets 120 a, 120 b to the vortex tube 118 and generates a vortex.

The input fluid travels through the vortex tube 118 in a vortical flowincluding a first fluid stream or portion of the input fluid and asecond fluid stream or portion of the input fluid. The first fluidstream has a higher temperature than the second fluid stream, such thatthe first fluid stream is a relatively hot fluid stream and the secondfluid stream is a relatively cold fluid stream. As an example of theoperation of the vortex tube 118, a vortex is created by spinning theinput fluid. This vortex may be considered a primary vortex consistingof the first fluid stream. The first fluid stream flows toward a firstend of the vortex tube 118, where a portion of the first fluid streamexits the vortex tube 118. The remainder of the first fluid stream, orthe second fluid stream, flows toward a second end of the vortex tube118. The second fluid stream travels as a secondary vortex inside alow-pressure area of the primary vortex. The first fluid stream and thesecond fluid stream flow in counter directions toward the first end andthe second end of the vortex tube 118, respectively, while rotating inthe same direction at the same angular velocity. Angular momentum islost from the secondary vortex to the primary vortex. This loss ofenergy results in a temperature difference between the first fluidstream and the second fluid stream such that the temperature of thefirst fluid stream is increased as compared to the temperature of thesecond fluid stream.

For example, the temperature of the hot fluid stream may be about 120°F. greater than the temperature of the input fluid entering the vortextube inlets 120 a, 120 b. The temperature difference between the hotfluid stream and the input fluid may be greater or less than 120° F.When the temperature difference between the hot fluid stream and theinput fluid is about 120° F., the temperature difference between thecold fluid stream and the input fluid is about 60° F. In such examples,the temperature of the cold fluid stream is about 60° F. less than thetemperature of the input fluid. The temperature difference between thehot fluid stream and/or the cold fluid stream with respect to the inputfluid is related to output flows of the hot fluid stream and the coldfluid stream from the vortex tube 118, as will be discussed furtherherein.

In the apparatus 100, the hot fluid stream flows through the vortex tube118 and exits the apparatus 100 via a hot fluid outlet 122.Additionally, a vortex tube valve 124 is disposed in the vortex tube 118such that the hot fluid stream flows across the vortex tube valve 124before exiting the apparatus 100 via the hot fluid outlet 122. The coldfluid stream exits the vortex tube 118 through a cold fluid outlet 126opposite the hot fluid outlet 122. In some examples, a second vortextube valve is disposed in the cold fluid outlet 126 to control theoutput of the cold fluid stream.

As the stem 110 controls or adjusts the regulator valve 108 to regulatethe pressure of the process fluid flowing through the regulator 102, thestem 110 also controls or adjusts the vortex tube valve 124 to provideheat to the regulator valve 108 relative to a demand on the regulator102. In jointly controlling the regulator valve 108 and the vortex tubevalve 124 in the regulator body 104, the single stem 110 controls theregulator valve 108 to maintain a constant output pressure of theprocess fluid exiting the regulator 102 via the regulator outlet 112.The stem 110 also controls the vortex tube valve 124 to transfer heatfrom the hot fluid stream to the regulator valve 108. Further, the stem110 controls the vortex tube valve 124 such that the temperaturedifference between the hot fluid stream and the input fluid entering thevortex tube 118 is maximized relative to a pressure reduction of theprocess fluid at the regulator valve 108.

To maintain a constant pressure output of the process fluid exiting theregulator 102 via the regulator outlet 112, the stem 110 adjusts theposition of the regulator valve 108 in response to the behavior of theloading mechanism 114 and the sensing element 116. The stem 110 opensthe regulator valve 108 to increase an amount of flow of the processfluid through the regulator 102 when the sensing element 116 isdisplaced due to a force generated by the loading mechanism 114 that isgreater than a force corresponding to the process fluid in the secondregulator chamber 102 b. The stem 110 closes the regulator valve 108 torestrict flow of the process fluid through the regulator 102 when theforce from the loading mechanism 114 against the sensing element 116 isless than the force corresponding to the process fluid in the secondregulator chamber 102 b. The stem 110 controls the regulator valve 108to maintain a constant output pressure at the regulator outlet 112 asdefined by the loading mechanism 114.

To provide heat to the regulator valve 108, the input fluid enters thevortex tube 118 via the vortex tube inlets 120 a, 120 b and a vortex isgenerated in the vortex tube 118. The vortex includes the hot fluidstream, which has a temperature that is higher than a temperature of theinput fluid at the vortex tube inlets 120 a, 120 b. When the regulatorvalve 108 is open, the stem 110 positions the vortex tube valve 124 suchthat a portion of the hot fluid stream exits the vortex tube valve 124.Upon passing through the vortex tube valve 124, the hot fluid streamenters an expansion chamber 128 disposed in the regulator body 104 andpositioned between the vortex tube 118 and the hot fluid outlet 122. Inthe apparatus 100 shown in FIG. 1, the expansion chamber 128 is disposedin the regulator body 104 proximate to the first regulator chamber 102a.

A seal 130 is disposed between the regulator 102 and the expansionchamber 128. The seal 130 prevents mixing of the process fluid flowingthrough the first regulator chamber 102 a with the input fluid flowingthrough the vortex tube 118. The seal 130 may comprise an elastomericmaterial to permit the stem 110 to slide between the regulator 102 andthe vortex tube 118 to control the opening and closing the regulatorvalve 108 and the vortex tube valve 124. For example, the seal 130 maycomprise an elastomeric O-ring.

As the hot fluid stream flows into the expansion chamber 128, heat istransferred from the hot fluid stream to the process fluid in the firstregulator chamber 102 a. In the example apparatus 100, the heat istransferred via conduction. In particular, the heat is transferredthrough an area of contact 132 between the regulator 102 and theexpansion chamber 128. The area of contact 132 includes a surface 134 ofthe regulator 102. The surface 134 includes a thermally conductivematerial, such as a metal having a high heat transfer coefficient. Insome examples, the surface 134 includes fins to increase the surfacearea of the surface 134 and thereby increase a rate of heat transfer. Asheat is conducted through the surface 134 to the process fluid flowingthrough the first regulator chamber 102 a, the process fluid is heated.As the heated process fluid flows across the regulator valve 108, theformation of hydrates at the regulator valve 108 is reduced and/orprevented.

The stem 110 also controls the amount of flow of the hot fluid streamthrough the vortex tube valve 124 to provide for a maximum amount ofheat transferred to the process fluid relative to a magnitude of apressure drop of the process fluid at the regulator valve 108. Indetermining the amount of heat transferred to the process fluid relativeto the magnitude of the pressure drop occurring at the regulator valve108, the behavior of flow of the vortex in the vortex tube 118 isconsidered. In particular, the temperature difference of the hot fluidstream and the cold fluid stream with respect to the input fluidentering the vortex tube 118 and the flow of the vortex fluid throughthe vortex tube 118 may be represented by the example graph of FIG. 2.The graph of FIG. 2 shows temperature difference between an input fluidentering a vortex tube and a cold fluid stream and a hot fluid stream ofthe vortex versus a percentage of total flow of the cold fluid streamthrough a cold fluid outlet of the vortex tube.

As shown in the graph of FIG. 2, an inverse relationship exists betweenthe temperature of the hot fluid stream of the vortex and an amount offlow of the hot fluid stream exiting the vortex tube 118 via the hotfluid outlet 122. For example, when flow of the cold fluid streamthrough the cold outlet comprises about 80% of a total output flow and,thus, flow of the hot fluid stream through the hot outlet comprisesabout 20% of the total output flow, the temperature difference betweenthe hot fluid stream and an input fluid is about 120° F. For the sameflow, the temperature difference between the cold fluid stream and theinput fluid is about −60° F.

The graph of FIG. 2 further shows that when flow of the cold fluidstream through the cold outlet comprises about 40% of the total outputflow and, thus, the hot fluid stream comprises about 60% of the totalflow, the temperature difference between the hot fluid stream and theinput fluid is about 40° F. For the same flow, the temperaturedifference between the cold fluid stream and the input fluid is about−120° F. As represented by the graph of FIG. 2, increased temperature ofthe hot fluid stream corresponds to decreased output flow of the hotfluid stream through the vortex tube.

In the apparatus 100, when the vortex tube valve 124 is nearly closedand there is less flow of the hot fluid stream out of the hot fluidoutlet 122 as compared to flow of the cold fluid stream out of the coldfluid outlet 126, the temperature of the hot fluid stream is increasedin accordance with the behavior of the vortex tube shown in the graph ofFIG. 2. As the stem 110 adjusts the regulator valve 108 in response toincreased demand on the regulator 102, the stem 110 further adjusts thevortex tube valve 124 to provide increased heat to the regulator valve108 to prevent icing that may result from the increased reduction ofpressure occurring at the regulator valve 108.

For example, in response to increased demand on the regulator 102, thestem 110 opens the regulator valve 108 to increase flow of the processfluid through the regulator 102 and maintain a constant process fluidoutput pressure at the regulator outlet 112. As the process fluid flowsacross the regulator valve 108, pressure of the process fluid isreduced. As pressure of the process fluid is reduced, the risk of icingdue to hydrates forming at the regulator valve 108 increases because ofthe increased drop in pressure.

To address the increased risk of icing, the stem 110 adjusts the vortextube valve 124 to provide a maximum amount heat to the regulator valve108 relative to the magnitude of the pressure drop occurring at theregulator valve 108. The stem 110 positions the vortex tube valve 124 sothat flow of the hot fluid stream across the vortex tube valve 124 isless than the flow of the cold fluid stream exiting the vortex tube 118via the cold fluid outlet 126. In such examples, the vortex tube valve124 is in a partially or nearly closed position. As the flow of theprocess fluid through the regulator 102 increases due to the opening ofthe regulator valve 108, the flow of the hot fluid stream through thevortex tube valve 124 decreases due to the partial closing the vortextube valve 124. As flow of the hot fluid stream decreases, thetemperature of the hot fluid stream in the vortex tube 118 increases.The heat from the hot fluid stream is transferred to the process fluidin the regulator 102 as the hot fluid stream exits the vortex tube 118.In the example apparatus 100, the transfer of heat is accomplished viaconduction at the area of contact 132.

The stem 110 controls the regulator valve 108 and the vortex tube valve124 to balance flow of the process fluid through the regulator 102, thetemperature of the hot fluid stream, and the amount of heat transferredto the regulator 102. In achieving such a balance, the stem 110 servesto maintain a constant regulator output pressure and to prevent theformation of hydrates in the regulator valve 108.

In some examples, the apparatus 100 includes insulation 136 disposed inthe regulator body 104 and surrounding the vortex tube 118. Theinsulation 136 reduces the transmission (e.g., loss) of heat resultingfrom the generation of the vortex in the vortex tube 118 to environmentsother than the regulator 102. In some examples, the insulation includesa sound absorbing material that converts sound energy generated by thevortex in the vortex tube 118 to heat. The insulation 136 including asound absorbing material may further surround the cold fluid outlet 126to reduce noise as the cold fluid stream exits the tube 118. Theinsulation 136 is not limited to the apparatus 100 and may be includedin the example apparatus disclosed herein.

In some examples, a plate 138 is disposed between the vortex tube valve124 and the hot fluid outlet 122 to reduce noise resulting fromgeneration of the vortex in the vortex tube 118. The plate 138 breaksdown jets of the hot fluid stream exiting the vortex tube 118 via thehot fluid outlet 122. In some examples, the plate 138 is a perforatedplate. In some examples, the sound-reducing plate 138 is additionally oralternatively disposed in the cold fluid outlet 126. The plate 138 isdisposed in the hot fluid outlet 122 and/or the cold fluid outlet 126 tonot plug the hot fluid outlet 122 and/or the cold fluid outlet 126.

FIG. 3 shows a second example apparatus 300 to provide heat to aregulator valve. The apparatus 300 includes the vortex tube 118 disposedin a regulator body 304. As an input fluid enters the vortex tube inlets120 a, 120 b through the nozzles 121 and travels through the vortex tube118, a vortex is generated including a relatively hot fluid stream andrelatively cold fluid stream. The vortex tube valve 124 regulates a flowof the hot fluid stream exiting the vortex tube 118. The cold fluidstream exits the vortex tube 118 through the cold fluid outlet 126.

In the apparatus 300, the stem 110 controls the regulator valve 108 andthe vortex tube valve 124. When the regulator valve 108 is open, forexample, to increase flow of a process fluid through the regulator 102to maintain a constant pressure output, the stem 110 positions thevortex tube valve 124 such that the hot fluid stream exits the vortextube 118 and flows into the expansion chamber 128 disposed in the body304 proximate to the surface 134 of the regulator 102. The surface 134has channels 336 a, 336 b disposed therein and the hot fluid streamflows from the expansion chamber 128 through the channels 336 a, 336 band into the first regulator chamber 102 a. Heat from the hot fluidstream is transferred to the process fluid through mixing of the hotfluid stream with the process fluid in the first regulator chamber 102a. As the process fluid mixes with the hot fluid stream and flows acrossthe regulator valve 108 to the second regulator chamber 102 b, heat isprovided to the regulator valve 108 to reduce and/or prevent theformation of hydrates.

To transfer a maximum amount of heat to the regulator valve 108 relativeto the demand on the regulator 102, the stem 110 controls the vortextube valve 124 in accordance with the behavior of the vortex tube 118represented in the example graph of FIG. 2. For example, when theregulator valve 108 is open and flow of the process fluid through theregulator 102 is increased, the stem 110 partially closes the vortextube valve 124 to provide heat to the regulator 102 via flow of the hotfluid stream through the channels 336 a, 336 b. The temperaturedifference between the input fluid and the hot fluid stream exiting thevortex tube 118 via the partially closed vortex tube valve 124 ismaximized in response to increased pressure reduction of the processfluid at the regulator valve 108.

The apparatus 300 provides for heat transfer to the regulator 102through mixing of the hot fluid stream with the process fluid in theregulator 102. To maximize an amount of heat transferred to theregulator 102, a restrictor 338, such as a restrictor valve, is disposedin the process fluid inlet 106. The restrictor 338 provides for apressure drop as the process fluid enters the process fluid inlet 106and flows into the first regulator chamber 102 a. The restrictor 338facilitates mixing of the hot fluid stream with the process fluid byreducing the pressure of the process fluid. In some instances, thepressure of the process fluid in the first regulator chamber 102 a ishigher than the pressure of the hot fluid stream exiting the vortex tubevalve 124 and flowing through the channels 336 a, 336 b. The restrictor338 provides for a pressure drop at the process fluid inlet 106 toreduce the pressure of the process fluid and facilitate mixing of theprocess fluid and the hot fluid stream. After flowing through therestrictor 338, the pressure of the process fluid in the first regulatorchamber 102 a is less than the pressure of the hot fluid stream afterflowing through the vortex tube 118 and the channels 336 a, 336 b. Uponmixing the hot fluid stream with the process fluid, heat is provided tothe regulator valve 108 as a mixture of the process fluid and the hotfluid stream flows across the regulator valve 108.

In some examples, the channels 336 a, 336 b comprise plates having holestherein. The hot fluid stream flows through the perforated plates andinto the first regulator chamber 102 a. The diameter of the platesforming the channels 336 a, 336 b is selected based on the magnitude ofa pressure drop of the hot fluid stream as the hot fluid stream flowsfrom the vortex tube 118 to the expansion chamber 128 via the vortextube valve 124. The size of the channels 336 a, 336 b may be selected sothat the hot fluid stream maintains a higher pressure than the processfluid as the hot fluid stream flows across the vortex tube valve 124,through the channels 336 a, 336 b, and into the first regulator chamber102 a. Further, although FIG. 3 shows the apparatus 300 having twochannels 336 a, 336 b, the apparatus 300 may include additional or fewerchannels.

FIG. 4 depicts a third example apparatus 400 for transferring heat to aregulator valve. The apparatus 400 includes the vortex tube 118 disposedin a regulator body 404. Vortex tube inlets 420 a, 420 b serve as inletsfor a process fluid to the vortex tube 118 and the regulator 102 via asingle flow path in the body 404. The process fluid enters the vortextube inlets 420 a, 420 b through nozzles 421 and travels through thevortex tube 118 where a vortex is generated prior to the process fluidflowing into the first regulator chamber 102 a. The vortex includes arelatively hot portion of the process fluid, or a hot process fluidstream, and a relatively cold portion of the process fluid, or a coldprocess fluid stream.

The vortex tube valve 124 controls a flow of the hot process fluidstream exiting the vortex tube 118. After exiting the vortex tube 118,the hot process fluid stream flows into the first regulator chamber 102a. During operation of the regulator 102, the hot process fluid streamflows across the regulator valve 108 to the second regulator chamber 102b and exits the apparatus 400 via the regulator outlet 112. In flowingthrough the vortex tube 118 prior to entering the regulator 102, theprocess fluid is heated as a result of the vortex generated in thevortex tube 118. The heat of the process fluid prevents instances oficing as fluid pressure is reduced at the regulator valve 108.

In the apparatus 400, the vortex tube inlets 420 a, 420 b serve asinlets for providing the process fluid to the vortex tube 118 and theregulator 102. The process fluid flows through the vortex tube 118 priorto entering the regulator 102. As a result, the stem 110 controls thevortex tube valve 124 to balance demand on the regulator 102 with anamount of heat transferred to the regulator 102. Specifically, the stem110 controls the vortex tube valve 124 to provide for sufficient inputof the hot process fluid stream to the regulator 102 to maintain aconstant pressure output at the regulator outlet 112. In adjusting thevortex tube valve 124 to provide for sufficient input to the regulator102, the stem 110 further controls the heat provided to the regulator102 based on temperature and an amount of flow of the hot process fluidstream through the vortex tube valve 124.

The stem 110 balances a degree to which the vortex tube valve 124 isopen to provide sufficient input to the regulator 102 with thetemperature of the hot process fluid stream as it exits the vortex tube118. In accordance with the behavior of the vortex output flow shown inthe example graph of FIG. 2, the stem 110 positions the vortex tubevalve 124 such that the temperature of the hot process fluid streamexiting the vortex tube valve 124 is maximized relative to the amount offlow of the process fluid required through the vortex tube valve 124 tomaintain a constant output pressure at the regulator outlet 112. In theapparatus 400, the stem 110 controls the vortex tube valve 124 toprovide sufficient input to the regulator 102 and sufficient heat toprevent the build-up of ice due to the reduction of the process fluid atthe regulator valve 108.

Additionally, the stem 110 controls the regulator valve 108 and thevortex valve 124 to provide for staged pressure drops across theapparatus 400. The staged pressure drops increase stability of theapparatus 400 by reducing the magnitude of the pressure drop at theregulator valve 108 as the hot process fluid stream flows through theregulator 102. For example, as the stem 110 adjusts the vortex tubevalve 124 to provide for adequate flow of the hot process fluid streamto the regulator 102, a first pressure drop occurs as the hot processfluid stream flows through the vortex tube valve 124 and into the firstregulator chamber 102 a. Upon entering the first regulator chamber 102a, the pressure of the hot process fluid stream is reduced due to thefirst pressure drop at the vortex tube valve 124. When the hot fluidstream flows across the regulator valve 108, a second pressure drop atthe regulator valve 108 occurs. The magnitude of the second pressuredrop is less than if the hot process fluid stream had not encounteredthe first pressure drop, as the pressure of the hot process fluid streamwas reduced at the vortex tube valve 124 before flowing into the firstregulator chamber 102 a. The first pressure drop at the vortex tubevalve 124 allows for smaller sizing of the loading mechanism 114 and thesensing element 116 to balance forces corresponding to the loadingmechanism 114 and the process fluid. As a result, the stability of theapparatus 300 is increased due to the staged pressure drops at the twovalve seats in the regulator body 404.

FIG. 5 is a second, more detailed operational view of the exampleapparatus 400. FIG. 5 shows the flow of an input process fluid 442through the vortex tube 118 and the behavior of the stem 110. As theinput process fluid 442 enters the vortex tube inlets 420 a, 420 bthrough the nozzles 421, a vortex 444 is generated. The vortex 444includes a relatively hot process fluid stream 444 a and a relativelycold process fluid stream 444 b.

In the apparatus 400 depicted in FIG. 5, the stem 110 controls theopening and closing of the regulator valve 108 and the vortex tube valve124 in response to demand on the regulator 102 to maintain pressureoutput and prevent icing. As demand on the regulator increases, the stem110 opens the regulator valve 108. Further, the stem 110 positions thevortex tube valve 124 such that the temperature difference between thehot process fluid stream 444 a and the input process fluid 442 ismaximized relative to the amount of flow of the input process fluid 442required through the apparatus 400 to maintain a constant pressureoutput at the regulator outlet 112.

As demand on the regulator 102 decreases, the stem 110 causes theregulator valve 108 to close. In such instances, the stem 110 moves thevortex tube valve 124 to a more fully open position such that thetemperature difference between the hot process fluid stream 444 a andthe input process fluid 442 is less than when the vortex tube valve 124is partially closed. During operation of the apparatus 400, the stem 110continuously adjusts the regulator valve 108 and the vortex tube 124based on the demand on the regulator 102.

In the apparatus 400, the cold fluid stream exits the tube 118 throughthe cold fluid outlet 126. In some examples, the cold fluid stream flowsinto, for example, pipes located downstream from the example apparatus400. In some examples, the cold fluid stream 444 b is air that isreleased to the atmosphere. Further, in the example apparatus 100 and300, the cold fluid streams may additionally be captured or releasedupon exiting the cold fluid outlet 126 in the manner as described forthe example apparatus 400.

In some examples, a detwister 446 is disposed in the vortex tube 118proximate to the vortex tube valve 124. The detwister 446 straightensthe hot process fluid stream 444 a prior to the hot process fluid stream444 a flowing across the vortex tube valve 124. In straightening the hotprocess fluid stream 444 a, the detwister 446 facilitates separation ofthe hot process fluid stream 444 a from the cold process fluid stream444 b. In separating the hot process fluid stream 444 a and the coldprocess fluid stream 444 b, the detwister 446 provides for increasedheat output as the hot process fluid stream 444 a exits the vortex tube118 through the vortex tube valve 124. The detwister 446 is not limitedto the example apparatus 400 as shown in FIG. 5. The detwister 446 mayalso be implemented in the example apparatus 100 and the exampleapparatus 300. Other mechanisms for separating the hot process fluidstream 444 a from the cold process fluid stream 444 b may also beimplemented in the example apparatus disclosed herein.

FIG. 6 shows the example apparatus 100 having a lever 650 to control thevortex tube valve 124. The lever 650 is disposed in the regulator body104 between the seal 130 and the vortex tube 118. The lever 650 isconnected to the stem 110 such that the lever 650 adjusts the vortextube valve 124 in response to the behavior of the stem 110 in adjustingthe regulator valve 108 due to a force from the loading mechanism 114.

In the apparatus 100, the stem 110 opens the regulator valve 108 toprovide for increased flow of the process fluid through the regulator102 to maintain a constant pressure output at the regulator outlet 112.Concurrently, the lever 650 causes the vortex tube valve 124 topartially close to provide for the transfer of heat to the regulatorvalve 112 via the hot fluid stream of the vortex generated in the vortextube 118. For example, heat may be transferred to the regulator 102through conduction via the area of contact 132 between the regulator 102and the expansion chamber 128.

In some examples, the position of vortex tube 118 in the regulator body104 is offset relative to a position of the stem 110 and the seal 130.Offsetting the position of the vortex tube 118 accommodates motion of anarm of the lever 650 as the lever 650 controls the opening and closingof the vortex tube valve 124.

The lever 650 is not limited to the example apparatus 100 as shown inFIG. 6. Rather, the lever 650 may be implemented to provide for thetransfer of heat to the regulator via the mixing of fluids as in theexample apparatus 300 or via serial flow of the input fluid as in theexample apparatus 400. Further, the lever 650 may be configured with thestem 110 in implementations other than the arrangement shown in FIG. 6.

From the foregoing, it will be appreciated that the above disclosedexample apparatus include a regulator and vortex generator disposed inone body to regulate pressure and provide heat to reduce or preventinstances of icing at the point of pressure reduction in the regulatorthat may hinder the performance of the regulator. The examples disclosedabove provide for the transfer of heat to the regulator without the needfor external sources of heat and without temperature loss to theenvironment that may result from connecting external heat sources to theregulator. Heat is efficiently transferred to the regulator through, forexample, conduction, fluid mixing, or serial flow of fluid through thevortex generator and the regulator. Further, the vortex generator doesnot require any other sources to generate heat other than a compressedfluid. In some examples, the compressed fluid provided to the vortexgenerator may be the same fluid that is output from the regulator.

Additionally, the examples apparatus disclosed herein maintain aconstant output pressure at the regulator outlet. Further, the exampleapparatus disclosed above provide for a maximum amount of heattransferred to the regulator relative to the demand on the regulator andthe magnitude of pressure reduction occurring at the regulator valve,which may correspond to an increased risk of icing. A two-seat, singlestem valve stem allows for control of both the regulator and the vortexgenerator to provide for real-time adjustment with respect to the heatsupplied to the regulator in response changes in flow through theregulator. It will be appreciated that the single stem balances anamount of flow through the regulator required to maintain a constantoutput pressure with an amount of heat transferred to the regulator toprevent icing resulting from pressure reduction of a fluid in theregulator.

Further, a staged pressure drop increases stability of the exampleapparatus disclosed herein by providing for a first pressure drop of afluid as the fluid exits the vortex generator and flows to theregulator. The first pressure drop reduces the magnitude of the pressuredrop of the fluid required at the regulator valve to maintain a constantregulator pressure output. The staged pressure drop allows for a smallerloading mechanism and sensing element to be used with the exampleapparatus without sacrificing stability of the regulator and whilepreventing the formation of hydrates that may impede regulatorperformance.

Although certain example methods, apparatus and articles of manufacturehave been disclosed herein, the scope of coverage of this patent is notlimited thereto. On the contrary, this patent covers all methods,apparatus and articles of manufacture fairly falling within the scope ofthe claims of this patent.

What is claimed is:
 1. An apparatus, comprising: a housing including aninlet, an outlet, a first valve, and a stem disposed therein; a vortexgenerator disposed in the housing, a fluid to flow from the inletthrough the vortex generator; and a second valve disposed in the vortexgenerator, the vortex generator to generate heat prior to the fluidflowing through the second valve to the outlet, the stem to control thefirst valve and the second valve to regulate an amount of the heatconveyed to the first valve.
 2. The apparatus of claim 1, wherein thehousing is to substantially enclose the stem and the vortex generator.3. The apparatus of claim 1, further including a first chamber and asecond chamber disposed in the housing, the first valve disposed betweenthe first chamber and the second chamber.
 4. The apparatus of claim 3,wherein the fluid is to flow from the vortex generator to the firstchamber via the second valve.
 5. The apparatus of claim 3, wherein thesecond chamber includes the outlet.
 6. The apparatus of claim 1, whereinthe outlet is a first outlet and the housing includes a second outlet,the second outlet to convey a portion of the fluid away from the firstvalve via the vortex generator.
 7. The apparatus of claim 1, furtherincluding a detwister disposed in the vortex generator, the fluid toflow through the detwister before flowing through the second valve. 8.The regulator of claim 1, wherein the stem is to position the firstvalve in a first position and the second valve in a second position toregulate the amount of heat conveyed to the first valve, the firstposition different from the second position.
 9. A regulator, comprising:a body having an inlet, an outlet, a first valve, and a stem disposedtherein, a fluid to flow from the inlet to the outlet; a vortex tube toheat the fluid prior to the fluid flowing through the first valve, thestem and at least a portion of the vortex tube disposed in an interiorof the body; and a second valve disposed in the vortex tube, the stem tocontrol the first valve and the second valve to regulate an amount ofthe fluid flowing from the vortex tube to the first valve.
 10. Theregulator of claim 9, wherein the inlet is a first inlet and furtherincluding a second inlet, each of the first inlet and the second inletto provide the fluid to the vortex tube.
 11. The regulator of claim 9,further including a first chamber and a second chamber disposed in thebody, the first valve disposed between the first chamber and the secondchamber, the vortex tube disposed proximate to the first chamber. 12.The regulator of claim 11, wherein the vortex tube includes a first endand a second end, the first end to provide an inlet for a first portionof the fluid to enter the first chamber, the second end to provide anoutlet for a second portion of the fluid.
 13. The regulator of claim 9,wherein the first inlet includes a nozzle to spin the fluid prior to thefluid flowing into the vortex tube.
 14. The regulator of claim 9,wherein the stem is to control the first valve and the second valvebased on a pressure at the outlet.
 15. The regulator of claim 9, furtherincluding insulation disposed in the body proximate to the vortex tube.16. An apparatus, comprising: means for regulating pressure of a fluid;means for heating the means for regulating pressure; first means forcontrolling a first flow of the fluid from the means for heating to themeans for regulating pressure; second means for controlling a secondflow of the fluid at the means for regulating pressure; and means forpositioning the first means for controlling and the second means forcontrolling, the means for regulating pressure, the means for heating,and the means for positioning disposed in one body.
 17. The apparatus ofclaim 16, wherein the means for heating includes a vortex tube.
 18. Theapparatus of claim 17, wherein the first means for controlling isdisposed in the vortex tube.
 19. The apparatus of claim 16, wherein themeans for positioning is to position the first means for controlling andthe second means for controlling based on an amount of heat to beconveyed to the second means for controlling.
 20. The apparatus of claim16, further including an inlet, the inlet to deliver the fluid to themeans for heating and the means for regulating pressure.